Cube Enhancements (Analysis Services)
Microsoft SQL Server 2005 Analysis Services (SSAS) includes the following cube enhancements and new features.
Key Performance Indicators
Analysis Services provides customizable business metrics called Key Performance Indicators (KPIs), which consist of relevant attributes and associated calculations that generate industry-standard goals and benchmarks. A KPI collection includes a measure, a goal, display properties, and variances. Companies use KPIs to track performance and improve decision-making. For more information, see Key Performance Indicators.
Multiple Fact Tables
Analysis Services now supports multiple fact tables within a single cube through the use of measure groups. Measures from a single fact table are grouped together in a measure group, and a single cube can contain multiple measure groups. Measure groups are also used to associate dimensions with measures, in order to hierarchically organize the measures that the measure group contains. For more information, see Unified Dimensional Model.
Business Intelligence Enhancements
Analysis Services provides business intelligence enhancements such as currency conversion, dimension writeback, and account and time intelligence, all of which can be added to cubes. For more information, see Defining Time Intelligence Calculations using the Business Intelligence Wizard and Enhancing a Dimension using the Business Intelligence Wizard.
Analysis Services now includes perspectives, which are pre-defined viewable subsets of cube metadata. Similar to a view in SQL Server 2005, a perspective can reduce the perceived complexity of a cube in Analysis Services by letting you define a viewable subset of the cube. The perspective controls how the objects contained by a cube, including measure groups, measures, dimensions, hierarchies, attributes, KPIs, actions, and calculations, are visible to a business intelligence application. You can use perspectives to provide a focused, business-specific or application-specific viewpoint on a cube. For more information, see Perspectives.
Analysis Services includes more support for aggregating measures across some dimensions and not others. The Analysis Services engine lets you specify the aggregation function to use for each dimension, and then infers the appropriate aggregation function for each measure based on the account type of the dimension. Alternatively, you can specify aggregation functions explicitly for each measure for a particular dimension. Semi-additive measures enable aggregation for an account dimension to be set by account. Standard account types that correspond to particular aggregation methods can be assigned to different accounts. Business users can then set up cubes that reflect a company's account structure, without writing custom rollup formulas. For more information, see Measures and Measure Groups.